True fact: I failed out/dropped out of grad school in mathematics. But despite having little enthusiasm for topology or complex analysis, nothing drives me more nuts than people who say stuff like â€œIâ€™m not good at math â€“ just not a math person, I guess.â€ This attitude is not just incorrect, itâ€™s harmful. Most mathematics is quite straight-forward, if you practice and study conscientiously. Same with ECGs.
Stratford EMS was called for a (quite) elderly woman who wasnâ€™t feeling well. And of course, she lived on the 5th floor of a building with narrow, twisting stairs. Nonetheless, the paramedic Jay and his crew humped all their gear, including the Like-Pak, up those stairs. Good thing too.
There was a small language barrier, but Jay ascertained that the woman was complaining of a â€œburningâ€ in her epigastrium that she also felt in her back. This had started within the last hour. VS were normal, as was the exam, except that she â€œdidnâ€™t look right.â€ Time for the 12-lead!
Does it meet STEMI criteria? Thereâ€™s a bunch of ST segment depression in the inferior and lateral leads, but (as you all know) that doesnâ€™t usually count for field activation. There is ST segment in aVL, but it is < 1mm, and aVR shows only minor STE, while lead I shows none.
V2 and V3 show some STE, but it isnâ€™t much, and it would have been easy for Jay to tell himself that, since the computer didnâ€™t â€œseeâ€ it, it wasnâ€™t really there. Instead, he turned his attention to V4â€¦.
â€¦ and noted that the T wave seemed pretty darn tall, relative to the R wave. Along with a hint of STD in V3, it triggered Jay to consider a de Winter-ish pattern.
The strict de Winter criteria require more ST depression, however, at least 1 mm, and we already have minor (but significant) anterior STE, so this ECG isnâ€™t a â€œpureâ€ example. However the morphology of V4 is pretty similar to that seem in a number of cases that Dr. de Winter evaluated, and who all turned out to have proximal LAD occlusions:
This pattern convinced Jay to call this in as a STEMI, activating the cath lab from the field. To be specific, activating it from the 5th-floor back bedroom.
Good thing too â€“ it was â€œafter-hours,â€ and the cardiology team needed time to get in to the lab form home. Also, extrication turned out to be a flail, squeezing the patient down narrow, winding stairs.
A second ECG obtained 10 minutes later, during the perilous descent to the rig:
The computer still doesnâ€™t get it, but the ST segments in both lead I and V3 have started to straighten and move up, suggesting that the first diagonal is occluded, likely because the proximal LAD is blocked.
The Life-Pak finally made the call 15 minutes after the initial ECG. By this time, however, the patient was starting to look a lot worse, and the pressure was dropping. A fluid bolus was given, keeping the SBP barely above 90.
By the time the rig was pulling into the ED, 30 minutes after the initial ECG, the 12-lead wouldnâ€™t have been missed by an EMT-B student during their ED observation time. At this point, however, the patient was in frank cardiogenic shock, and the Stratford EMS team was directed to bypass the ED, since they had given the cath team sufficient heads-up to prep the lab. Without the “bedroom-activation” that Jay made, this patient could have arrested while waiting in the ED.
Bring your gear in on every call. Every call.
Navy SEALS donâ€™t leave their gear behind while they â€œjust go check it out first,â€ and neither should EMS. A paramedic without their gear, and especially without their monitor/defib, is not that helpful.
Get serial ECGs when you suspect something.
Donâ€™t be satisfied if the computer â€œdidnâ€™t say there was a STEMI.â€
Practice, practice, practice your ECG skills! Jay felt comfortable committing to the early activation because he has worked hard at reading 12-leads, seeking feedback, and pushing his skills. He has developed a “gut sense” after hours of study, and hundreds of ECGs. He hasnâ€™t been afraid to ask questions, accept criticism, and learn.